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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-812 4 Washington Zone 15 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-08   
301-812 5 Washington Zone 15 (Baltimore LATA) MD   829J PAETEC ITEL, LLC 238   2013-08-28   
301-812 6 Washington Zone 15 (Baltimore LATA) MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2013-11-26   
301-812 7 Washington Zone 15 (Baltimore LATA) MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2010-10-04   
301-812 8 Washington Zone 15 (Baltimore LATA) MD BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-22   
301-812 9 Washington Zone 15 (Baltimore LATA) MD   829J PAETEC ITEL, LLC 238   2004-01-31   
301-813 A Washington Zone 2 MD VINNVACB2MD  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 236      
301-814 A Washington Zone 2 MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-815 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-816 A Washington Zone 11 MD RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-817 A Washington Zone 5 MD STLDMDSLDS0  9212 VERIZON MARYLAND, INC. 236      
301-818 A Waldorf MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236      
301-819 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-820 A Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 0 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   
301-820 1 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   
301-820 2 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-09-14   
301-820 3 Gaithersburg MD   829J PAETEC ITEL, LLC 236   2011-05-27   
301-820 4 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 5 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2009-11-04   
301-820 6 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 7 Gaithersburg MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2011-06-17   
301-820 8 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   
301-820 9 Gaithersburg MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-01-07   
301-821 A Laurel MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-821 0 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2006-01-02   
301-821 1 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2006-01-02   
301-821 2 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2006-08-07   
301-821 3 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2005-09-20   
301-821 4 Laurel MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-821 5 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2005-09-20   
301-821 6 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2006-01-02   
301-821 7 Laurel MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2006-01-02   
301-821 8 Laurel MD LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236   2005-11-17   
301-821 9 Laurel MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-11-08   
301-822 A Washington Zone 11 MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-822 0 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 1 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-822 2 Washington Zone 11 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-02-09   
301-822 3 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 4 Washington Zone 11 MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2013-10-03   
301-822 5 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 6 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-822 7 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 8 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 9 Washington Zone 11 MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236      
301-823 A Washington Zone 13 MD WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-823 0 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-02-01   
301-823 1 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-02-01   
301-823 2 Washington Zone 13 MD WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236   2008-10-10   

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Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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